Field of the Invention
The present invention relates to a wheel loader.
Background Information
An exhaust gas post-treatment device is mounted on a wheel loader. The exhaust gas post-treatment device includes a diesel particulate filter device that collects and removes particulate matter of smoke and the like included in the diesel engine exhaust gas. The diesel particulate filter device is mounted in a row with an air cleaner above the engine. A nitrogen oxide reduction catalyst device may also be provided to remove NOx from the exhaust gas. The nitrogen oxide reduction catalyst device is provided on the exhaust downstream side of the diesel particulate filter device.
As described above, while the diesel particulate filter device is disposed with the air cleaner above the engine, the installation location of the nitrogen oxide reduction catalyst device becomes a problem when the nitrogen oxide reduction catalyst device is installed along with the diesel particulate filter device. Because the nitrogen oxide reduction catalyst device needs to be disposed on the exhaust downstream side of the diesel particulate filter device, generally the nitrogen oxide reduction catalyst device is mounted in a row with the air cleaner and the diesel particulate filter device above the engine when the nitrogen oxide reduction catalyst device is installed along with the diesel particulate filter device.
However, a problem arises with the spatial relationship when the air cleaner, the diesel particulate filter device, and the nitrogen oxide reduction catalyst device are all disposed in a row above the engine. Therefore, although the disposition of a relatively light air cleaner above the diesel particulate filter device and the nitrogen oxide reduction catalyst device may be considered, the top plate of the engine room becomes higher in this case and visibility to the rear is reduced.
Accordingly, a configuration has been proposed for a large-scale dump truck described in Japanese Patent Laid-open No. 2003-335268 in which an engine room is provided beside the cab and an air cleaner is disposed on the outside of the engine room. With such a configuration, visibility to the rear is not reduced when the air cleaner is disposed on the upper portion of the engine room.
However, because the engine room is disposed to the rear of the cab in a wheel loader, visibility to the rear may become reduced if the configuration described in Japanese Patent Laid-open No. 2003-335268 is applied as-is to the wheel loader. Further, the air cleaner needs to be disposed to allow for ease of maintenance work because the filter inside the air cleaner requires regular cleaning and exchanging at certain time periods.
An object of the present invention is to prevent a reduction in visibility to the rear and to enable ease of maintenance work in a wheel loader.
A wheel loader according to a first aspect of the present invention is provided with a cab, a ladder, an expansion member, a vehicle body cover, an engine, and an air cleaner. The cab is provided with a driver seat inside the cab. The ladder is provided at a side of the cab. The ladder has a plurality of steps disposed with intervals therebetween. The expansion member assumes an expanded posture. The expansion member abuts at least one step and protrudes in the vehicle width direction when in the expanded posture. The vehicle body cover is disposed to the rear of the cab and demarcates an engine room. The engine is disposed inside the engine room. The air cleaner includes therein a filter that is exchangeable and cleans air supplied to the engine. The air cleaner is disposed outside of the vehicle body cover. The air cleaner is disposed above and to the rear of the expansion member when the expansion member assumes the expanded posture.
The air cleaner in the wheel loader is provided on the outside of the vehicle body cover and is not provided in the engine room. According to this configuration, because the air cleaner is disposed outside of the engine room, a top plate of the engine room does not need to be made higher even when an exhaust gas post-treatment device is installed above the engine inside the engine room. Therefore, reduction in visibility to the rear can be avoided despite the installation of the exhaust gas post-treatment device.
Moreover, because the air cleaner is disposed above and to the rear of the expansion member while the expansion member assumes the expanded posture, maintenance work on the air cleaner can be performed by the operator while on the ladder and the maintenance work can be performed easily. The expansion member abuts at least one step when the expansion member assumes the expanded posture. As a result, the operator is able to work while standing on the at least one step and the expansion member. In this way, the operator is able to perform the air cleaner maintenance work in a stable posture because the foothold for the operator is widened when working.
The expansion member preferably assumes a retracted posture in which the expansion member is retracted from the at least one step. That is, the expansion member is able to assume the expanded posture and the retracted posture. According to this configuration, when the operator is not performing maintenance work, that is, when the ladder is used for climbing up to and down from the cab, the expansion member does not become an obstruction while climbing up to and down from the cab due to the retracted posture of the expansion member.
The at least one step preferably has a length in the vehicle front-back direction greater than that of the other steps. According to this configuration, the operator is able to perform the maintenance work on the air cleaner while maintaining a stable posture.
The air cleaner is preferably configured so that the filter can be pulled out toward the ladder and disposed to be inclined so that the pulling-out side of the filter is further away from the cab than the opposite side. According to this configuration, the operator is able to remove the filter easily while standing on the at least one step of the ladder.
The wheel loader preferably is further provided with a platform disposed at the side of the cab. The expansion member is positioned under the platform in the retracted posture. According to this configuration, the expansion member does not become an obstruction when the operator uses the ladder for climbing up to and down from the cab due to the expansion member being positioned below the platform.
The expansion member is preferably attached to the platform. According to this configuration, even when the ladder is deformed due to a collision, the expansion member can function effectively because the expansion member is attached to the platform and not to the ladder.
The expansion member preferably has a fixed part, an arm part, and a flat part. The fixed part extends downward from the platform. The arm part couples to the lower end part of the fixed part is a swingable manner. The flat part extends from the arm part in the vehicle front-back direction. The flat part abuts the at least one step in the expanded posture. According to this configuration, the expansion member is able to selectively assume the expanded posture and the retracted posture by swinging the arm part with respect to the fixed part.
The ladder preferably extends downward from the platform disposed at the side of the cab. A first step positioned at the top of the plurality of steps protrudes from the platform in the vehicle width direction. Steps other than the first step protrude in the vehicle width direction from one step above. A protrusion amount of each step is fixed.
According to this configuration, the operator is able to ascend and descend the steps of the ladder smoothly, the expansion member being positioned in the retracted posture.
The ladder preferably has a front strut and a rear strut that extend in the vertical direction and that are disposed away from each other in the vehicle front-back direction. The steps extend to cross between the front strut and the rear strut. The rear strut has an upper part and a lower part. The upper part of the rear strut has attached thereto a first step positioned at the top and a second step positioned second from the top among the plurality of steps. The lower part of the rear strut has another step attached thereto and the lower part is positioned further toward the front than the upper part.
According to this configuration, the first and second steps are attached to the upper part of the rear strut and the upper part of the rear strut is positioned further to the rear than the lower part. As a result, the first and second steps extend further to the rear than the other steps and the operator is able to perform the maintenance work in a position near the air cleaner. In this case, the at least one step corresponds to the first step or the second step.
The rear strut preferably further has a middle part that couples the upper part and the lower part. The middle part is inclined rearward in an upward direction as seen in a side view.
The wheel loader preferably further has a handrail member provided along the rear strut. The handrail member has a vertical part that extends vertically. The vertical part is positioned to the outside of the rear strut in the vehicle width direction. According to this configuration, because the vertical part of the handrail member is positioned to the outside of the rear strut in the vehicle width direction, the operator is able to perform the maintenance work while applying his weight onto the vertical part, and consequently is able to perform the maintenance work of the air cleaner while maintaining a more stable posture.
An upper edge of the handrail member is preferably positioned below the platform disposed at the side of the cab. According to this configuration, the operator will not trip over the handrail member while standing on the platform.
The ladder preferably further has a supplementary step that is below the step positioned at the bottom and that hangs down with elastic strips. According to this configuration, the operator is able to easily climb up to the step positioned at the bottom among the plurality of steps described above, and easily climb down from the step positioned at the bottom to the ground. Because the supplementary step is disposed in a position near the ground, the supplementary step or the elastic strips may collide with an obstruction on the ground. However, the elastic strips for suspending the supplementary step do not undergo plastic deformation.
The cab preferably has a cab body and a door. The rear part of the door is supported by the cab body. The door can be opened and closed toward the front. The air cleaner is disposed at a location that does not obstruct the door when the door is fully open.
According to this configuration, the door is not obstructed by the air cleaner when the driver opens or closes the door to enter or exit the cab.
The wheel loader preferably further includes an operating fluid tank disposed between the cab and the engine. The air cleaner is disposed at the side of the operating fluid tank.
According to this configuration, because the air cleaner is disposed outside of the engine room as described above, a reduction in visibility to the rear is avoided even when the exhaust gas post-treatment device is provided, and the maintenance work on the air cleaner can be performed easily.
The wheel loader is preferably provided with a rear wheel fender disposed above a rear wheel. The air cleaner is fixed to an upper part of the rear wheel fender.
According to this configuration, because the air cleaner is disposed outside of the engine room as described above, a reduction in visibility to the rear is avoided even when the exhaust gas post-treatment device is provided, and the maintenance work on the air cleaner can be performed easily as described above.
According to the present invention, a reduction in visibility to the rear is prevented and the maintenance work on the air cleaner can be performed easily.